The field of this invention relates to the welding of separate, coaxially located, edge abutting, metallic, cylindrical, tubular sections. More particularly, the field of this invention is directed to an apparatus for automatic gas tungsten arc welding along a circumferential path thereby securing separate tubes (or pipes) together forming essentially an integral, totally enclosed, tube.
The use of apparatuses to affect automatic welding of tubes has long been known. A common such apparatus is what is shown and described within U. S. Pat. No. 3,400,237, by the present invention. The apparatus of the present invention is to employ a weld technique similar to the aforesaid patent, and reference may be had to the aforesaid Patent for background information of the welding technique.
One of the inherent disadvantages of the aforesaid Patent is that the entire welding head is designed to be utilized in conjunction with a limited size range of tubes. In other words, a particular welding head would be designed for one-half inch tubes, while another welding head would be designed for three-quarter inch tubes. Each welding head is basically similar with the difference in the welding heads having to do with the structure that is attached to accommodate the particular size of tubes.
It would be highly advantages for efficient creating of welds and from a cost standpoint if a welding head apparatus could be constructed which divided the welding head into two separate parts. One part could contain the structure that is common to the welding procedure, regardless of the size of the tube being welded, and the other structure could pertain to the particular size of the tube being welded. The structures could then be attached together on a quick disconnect basis with the result that the overall welding head apparatus could be utilized on a wide variety of different size tubes rather than being restricted to a particular size of tubes.